The main page of the Beschulte
Group website as of 18 July shows only a white flag with the
wavy disc of the center. This symbol is shared by other
companies: Dorchester, Baltic Marine
Gdynia and possibly others.António Martins-Tuválkin, 17 January 2007

If we leave out the special case of the Muscovy Merchants, I believe the only
house flag not shown on FOTW-ws is that of the Red Rose Navigation Co. Ltd
(second row, central image):http://www.allatsea.cx/images/memorabilia/Peter_Murphy_House_Flags2.jpg
This firm is briefly mentioned here (url followed by quote):
http://www.theshipslist.com/ships/lines/holt.htm
"In 1965 the Guinea Gulf Line with a subsidiary of Holt, the Red Rose Navigation
Co. Ltd at Bermuda, was acquired by Elder Dempster Line Ltd..."
Elsewhere we learn that this company was established at Liverpool - just enter
"bocna" under "Name" and click "SEARCH" (later click "VIEW"):
http://www.hartlepoolbuilt.co.uk/form.html
I suppose Red Rose Navigation ('Bocna' was first named 'Rose of Lancaster' -
also look at the funnel) moved to Bermuda for fiscal reasons. Certainly active
1958-1965 but no other ship found yet.
I find it hard
to believe that the house flag was square but anyhow: dark blue field, large
white disk bearing a red rose seeded and barbed green.Jan Mertens, 21 June 2010